Anti-tumour necrosis factor α antibodies and circulating lymphocyte phenotypes in inflammatory bowel disease.

OBJECTIVE: Circulating lymphocyte subtypes are not fully explored parameters for monitoring chronic T cell activation during inflammatory bowel disease (IBD). Tumor necrosis factor α (TNFα), one of the main mediators of IBD related inflammation induces expression of CD70 on T cells. CD70 limits T cell expansion and controls CD27 receptor on activated B lymphocytes. Aim of this study was to assess the number and the frequency of CD70+ T cells and CD27+ B cells in IBD patients during inactive phase of the disease under or without anti-TNFα treatment. DESIGN: We studied 91 patients with inactive IBD, 31 untreated, 29 treated with infliximab (IFX), and 31 treated with adalimumab (ADA). Lymphocyte phenotypes were assessed by flow cytometry using anti-CD45, CD19, CD27, CD3, and CD70 monoclonal antibodies. IFX and ADA actual capacity of TNFα neutralization in serum was estimated by the recoveryELISA technique. RESULTS: Whereas CD3+ T cells were increased in treated compared to untreated patients, the percentage of the CD70+ T cells was significantly lower in treated patients indicating a 'cooling' effect of the biological therapy. This effect differs between samples according to the therapeutic range of the circulating drug. Although the CD19+ B-cell percentage tended to be lower in treated patients, CD19+27+ memory B cells did not show significant differences between groups. CONCLUSIONS: Frequency of peripheral blood CD70+ T cells was significantly reduced by treatment with anti-TNFα antibodies. Monitoring of this parameter of T cells can give better insight to the disease progression and therapy application in IBD patients.

SOX11, CD70, and Treg cells configure the tumor-immune microenvironment of aggressive mantle cell lymphoma.

Mantle cell lymphoma (MCL) is a mature B-cell neoplasm with a heterogeneous clinical and biological behavior. SOX11 oncogenic expression contributes to the aggressiveness of these tumors by different mechanisms, including tumor and stromal cell interactions. However, the precise composition of the immune cell microenvironment of MCL, its possible relationship to SOX11 expression, and how it may contribute to tumor behavior is not well known. Here, we performed an integrative transcriptome analysis of 730 immune-related genes combined with the immune cell phenotype analysis by immunohistochemistry in SOX11+ and SOX11- primary nodal MCL cases and non-neoplastic reactive lymph nodes. SOX11+ MCL had a significant lower T-cell intratumoral infiltration compared with negative cases. A reduced expression of MHCI/II-like and T-cell costimulation and signaling activation related transcripts was significantly associated with poor clinical outcome. Moreover, we identified CD70 as a SOX11 direct target gene, whose overexpression was induced in SOX11+, but not SOX11- tumor cells by CD40L in vitro. CD70 was overexpressed in primary SOX11+ MCL and it was associated with an immune unbalance of the tumor microenvironment characterized by increased number of effector regulatory t (Treg) cell infiltration, higher proliferation, and aggressive clinical course. CD27 was expressed with moderate to strong intensity in 76% of cases. Overall, our results suggest that SOX11 expression in MCL is associated with an immunosuppressive microenvironment characterized by CD70 overexpression in tumor cells, increased Treg cell infiltration and downmodulation of antigen processing, and presentation and T-cell activation that could promote MCL progression and represent a potential target for tailored therapies.

Desmoid tumors display a strong immune infiltration at the tumor margins and no PD-L1-driven immune suppression.

Desmoid tumors (DTs) are local aggressive neoplasms, whose therapeutic approach has remained so far unsolved and in many instances controversial. Nowadays, immunotherapy appears to play a leading role in the treatment of various tumor types. Characterization of the tumor immune microenvironment (TME) and immune checkpoints can possibly help identify new immunotherapeutic targets for DTs. We performed immunohistochemistry (IHC) on 33 formalin-fixed paraffin-embedded (FFPE) tissue sections from DT samples to characterize the TME and the immune checkpoint expression profile. We stained for CD3, CD4, CD8, CD20, FoxP3, CD45RO, CD56, CD68, NKp46, granzyme B, CD27, CD70, PD1 and PD-L1. We investigated the expression of the markers in the tumoral stroma, as well as at the periphery of the tumor. We found that most of the tumors showed organization of lymphocytes into lymphoid aggregates at the periphery of the tumor, strongly resembling tertiary lymphoid organs (TLOs). The tumor expressed a significant number of memory T cells, both at the periphery and in the tumoral stroma. In the lymphoid aggregates, we also recognized a significant proportion of regulatory T cells. The immune checkpoint ligand PD-L1 was negative on the tumor cells in almost all samples. On the other hand, PD1 was partially expressed in lymphocytes at the periphery of the tumor. To conclude, we are the first to show that DTs display a strong immune infiltration at the tumor margins, with formation of lymphoid aggregates. Moreover, we demonstrated that there is no PD-L1-driven immune suppression present in the tumor cells.

CD70 expression in tumor-associated fibroblasts predicts worse survival in colorectal cancer patients.

The anticancer effects of immune checkpoint inhibitors against CTLA4 and CD274-PDCD1 axes are evident. However, these immunotherapies for colorectal cancers (CRCs) are now limited to a small subset of patients with microsatellite unstable tumors. Thus, therapeutics targeting other types of CRCs is desired. The CD70-CD27 axis plays a co-stimulatory role in promoting the expansion and differentiation of T-lymphocytes through the activation of NFκB pathway. Aberrant activation of the CD70-CD27 axis accelerates tumor cell proliferation, survival, and immune evasion of tumor cells. Based on these observations, drugs modulating the CD70-CD27 axis have been developed with expectation of anticancer effects. In the present study, 269 primary CRCs were evaluated immunohistochemically for CD70, CD27, and FOXP3 expression to assess their clinical usage and the application of CD70-CD27 axis modulating drugs. CRC tumor cells rarely (2.2%) expressed CD70. In contrast, tumor-surrounding fibroblasts showed various CD70 expressions (fCD70) in 14.9%. The logistic regression analysis revealed significant association of fCD70 expression with incomplete resection status (OR, 2.60; 95% CI, 1.10-6.13; P = 0.029). Overall survival was significantly decreased in the cohort of the patients with fCD70-positive tumor (P = 0.0078). Furthermore, significantly more CD27+ tumor-associated lymphocytes were detected within the primary CRCs without metastases (P = 0.024). Thus, the CD70-CD27 axis may have several roles in CRCs independent from their mismatch repair (MMR) system status. CD70-CD27 pathway-modulating therapies may be applied to CRC patients regardless of their tumor MMR status.

Breast cancer stem cells characterized by CD70 expression preferentially metastasize to the lungs.

BACKGROUND: Cancer stem cells (CSCs) are believed to form metastases. We sought to determine whether CD70 + subpopulation in human breast cancers represents the CSCs accounting for distant metastasis. METHODS: We measured the expression levels of CD70 in breast cancer cell lines and 122 primary breast cancer samples. We characterized the functional roles of CD70 + subpopulation in distant metastasis of breast cancers. RESULTS: We observed a distinct pattern of CD70 expression in a panel of primary breast carcinoma samples, indicating that CD70 serves as a biomarker of lung-specific metastasis. CD70- and CD70+ cell populations isolated from breast cancer cell lines exhibited epithelial and mesenchymal phenotypes, respectively. CD70+ cells, but not CD70- cells, possessed self-renewal and differentiation potentials. Tumorsphere formation in suspension cultures and in vivo tumorigenicity were significantly greater in CD70+ cells than in CD70- cells. Furthermore, the development of lung metastases induced by orthotopic injection was markedly increased in mice inoculated with CD70 + cells. CD70 contributed to the promotion of lung metastases by enhancing self-renewal potential of CD70 + cells. CONCLUSIONS: We isolated CSCs from primary human breast cancers and found that CD70 + subpopulations mediate lung-specific metastasis. These findings might be used to aid in selection of patients for postoperative adjuvant therapy.

Dichotomous Expression of TNF Superfamily Ligands on Antigen-Presenting Cells Controls Post-priming Anti-viral CD4+ T Cell Immunity.

T cell antigen-presenting cell (APC) interactions early during chronic viral infection are crucial for determining viral set point and disease outcome, but how and when different APC subtypes contribute to these outcomes is unclear. The TNF receptor superfamily (TNFRSF) member GITR is important for CD4+ T cell accumulation and control of chronic lymphocytic choriomeningitis virus (LCMV). We found that type I interferon (IFN-I) induced TNFSF ligands GITRL, 4-1BBL, OX40L, and CD70 predominantly on monocyte-derived APCs and CD80 and CD86 predominantly on classical dendritic cells (cDCs). Mice with hypofunctional GITRL in Lyz2+ cells had decreased LCMV-specific CD4+ T cell accumulation and increased viral load. GITR signals in CD4+ T cells occurred after priming to upregulate OX40, CD25, and chemokine receptor CX3CR1. Thus IFN-I (signal 3) induced a post-priming checkpoint (signal 4) for CD4+ T cell accumulation, revealing a division of labor between cDCs and monocyte-derived APCs in regulating T cell expansion.

Tumor associated CD70 expression is involved in promoting tumor migration and macrophage infiltration in GBM.

Tumor migration/metastasis and immunosuppression are major obstacles in effective cancer therapy. Incidentally, these 2 hurdles usually coexist inside tumors, therefore making therapy significantly more complicated, as both oncogenic mechanisms must be addressed for successful therapeutic intervention. Our recent report highlights that the tumor expression of a TNF family member, CD70, is correlated with poor survival for primary gliomas. In this study, we investigated how CD70 expression by GBM affects the characteristics of tumor cells and the tumor microenvironment. We found that the ablation of CD70 in primary GBM decreased CD44 and SOX2 gene expression, and inhibited tumor migration, growth and the ability to attract monocyte-derived M2 macrophages in vitro. In the tumor microenvironment, CD70 was associated with immune cell infiltrates, such as T cells; myeloid-derived suppressor cells; and monocytes/macrophages based on the RNA-sequencing profile. The CD163+ macrophages were far more abundant than T cells were. This overwhelming level of macrophages was identified only in GBM and not in low-grade gliomas and normal brain specimens, implying their tumor association. CD70 was detected only on tumor cells, not on macrophages, and was highly correlated with CD163 gene expression in primary GBM. Additionally, the co-expression of the CD70 and CD163 genes was found to correlate with decreased survival for patients with primary GBM. Together, these data suggest that CD70 expression is involved in promoting tumor aggressiveness and immunosuppression via tumor-associated macrophage recruitment/activation. Our current efforts to target this molecule using chimeric antigen receptor T cells hold great potential for treating patients with GBM.

CD70 and PD-L1 in anaplastic thyroid cancer - promising targets for immunotherapy.

AIMS: During recent years, immune checkpoint inhibition has proved to be effective in several solid malignancies. The aim of this study was to identify novel targets for immunotherapy in anaplastic thyroid cancer by analysis of the expression of tumour antigens for which therapeutic agents are available. METHOD AND RESULTS: By immunohistochemistry we observed tumoral expression of CD70 in 49% of cases. Expression of its receptor, CD27, was present mainly in lymphocytes surrounding and infiltrating the tumour and observed only rarely in tumour cells. CD70 expression was associated with the presence of a precursor papillary thyroid carcinoma and the presence of BRAF V600E mutations in the anaplastic thyroid cancer lesion. Furthermore, the expression of CD70 seems stable during progression of the disease. Tumoral expression of programmed cell death ligand 1 (PD-L1) was found in 28.6% of the anaplastic thyroid cancer cases. Programmed cell death 1 (PD-1), the receptor of PD-L1, was not expressed on the tumour cells. No association between CD70 expression and PD-L1 expression could be demonstrated. CONCLUSION: These data suggest that targeted immunotherapy for CD70/CD27 and PD-L1/PD-1 might be promising in anaplastic thyroid cancer. However, as a low amount of tumour-infiltrating lymphocytes was observed in most lesions, combined therapy with agents enhancing the invasion of lymphocytes in the tumour region needs to be considered.

Melanoma-expressed CD70 is involved in invasion and metastasis.

BACKGROUND: CD70 is a costimulatory molecule of the tumour necrosis factor family expressed in activated immune cells and some solid tumours. In lymphocytes CD70 triggers T cell-mediated cytotoxicity and mitogen-activated protein kinase phosphorylation. METHODS: We evaluated the expression of CD70 in biopsies and melanoma cell lines. Using melanoma cell lines positive or not for CD70, we analysed CD70 function on melanoma progression. RESULTS: We report CD70 expression in human melanoma cell lines and tumour cells from melanoma biopsies. This expression was observed in 95% of primary melanomas but only 37% of metastases. Both monomeric and trimeric forms of CD70 were detected in tumour cell membrane fractions, whereas cytoplasmic fractions contained almost exclusively monomeric CD70. In vitro and in vivo experiments demonstrated that CD70 expression inhibited melanoma cell migration, invasion and pulmonary metastasis implantation independently of the tumour immune microenvironment. Increasing the levels of the trimeric form of CD70 through monoclonal antibody binding led to an increase in CD70+ melanoma cell invasiveness through MAPK pathway activation, RhoE overexpression, ROCK1 and MYPT1 phosphorylation decrease, and stress fibres and focal adhesions disappearance. CONCLUSIONS: Our results describe a new non-immunological function of melanoma-expressed CD70, which involves melanoma invasiveness through MAPK pathway, RhoE and cytoskeletal modulation.

High functional CD70 expression on α-type 1-polarized dendritic cells from patients with chronic lymphocytic leukaemia.

Antigen-loaded dendritic cells (DCs) used as anticancer vaccine holds promise for therapy, but needs to be optimized. The most frequently described DC vaccine is being matured with a cocktail containing prostaglandin E2 (PGE2 DC). However, even though PGE2 DCs express both costimulatory and migratory receptors, their IL-12p70-prodcution is low, leading to an insufficient Th1 immune response. As an alternative, α-type-1 polarized DCs (αDC1s) have shown a superior production of IL-12p70 and subsequent activation of effector cells. From chronic lymphocytic leukaemia (CLL) patients, αDC1s can be generated to induce a functional Th1-immune response. Yet, another costimulatory receptor, CD70, appears to be essential for optimal DC function by promotion of T cell survival and function. So far, PGE2 is suggested as one of the most important factors for the induction of CD70 expression on DCs. Therefore, we wanted to investigate whether αDC1s have the ability to express functional CD70. We found that CD70 expression on αDC1s could be upregulated in the same manner as PGE2 DCs. In an allogeneic mixed leucocyte reaction, we found that antibody-blocking of CD70 on αDC1s from controls reduced effector cell proliferation although this could not be found when using CLL αDC1s. Nevertheless, CD70-blocking of αDC1s from both controls and patients with CLL had a negative influence on the production of both IL-12p70 and the Th1 cytokine IFN-γ, while the production of the Th2 cytokine IL-5 was enhanced. Together, this study further suggests that αDC1s should be considered as a suitable candidate for clinical antitumour vaccine strategies in patients with CLL.

CD70 is selectively expressed on Th1 but not on Th2 cells and is required for Th1-type immune responses.

The interaction between CD27 and CD70 provides a costimulatory signal for T-cell survival. Although the role of CD27 signaling in CD8(+) T cells has been well defined, its role in CD4(+) T cells is relatively unknown. Here, we report that CD70 is specifically expressed on differentiated T-helper (Th)1 cells, but not on Th2 cells. Upon activation, CD70 expression increased markedly on Th1 cells, but remained undetectable on Th2 cells. We demonstrate that CD27 is involved in naive T-cell expansion in Th1-type, but not in Th2-type, immune responses as in vivo treatment with anti-CD70 monoclonal antibody at induction resulted in a significant reduction of delayed-type and contact hypersensitivity responses, but not asthmatic responses. In both Th1-type responses, during the priming phase, CD70 was detected at earlier time points on dendritic cells (DCs) and at later time points on CD4(+) T cells. Our results indicate that CD70 may be useful as a marker to distinguish Th1 from Th2 cells. More importantly, CD27 function may be controlled by the differentially regulated kinetics of CD70 expression on DCs and CD4(+) T cells, and Th1 cell-specific CD70 expression may be involved in an amplification loop for polarized Th1-type immune responses through T cell-T cell interactions.

Uric acid directly promotes human T-cell activation.

BACKGROUND: Abnormally high serum uric acid levels have been associated with several disease conditions including gout and kidney stone disease. More recently, it was shown that uric acid crystals stimulate dendritic cell maturation, activate the NALP3 inflammasome, and enhance antigen-specific immune responses. We hypothesize that uric acid can also stimulate T cells directly and in the absence of antigen presentation. METHODS: Purified primary human T cells were incubated with and without uric acid at concentrations of 50, 100, 150, and 200 microg/mL. The expression of T-cell activation markers CD25 and CD70 was assessed by flow cytometry. In other experiments, Jurkat T cells were used and the expression of the costimulatory molecule CD70 was determined at the mRNA level. RESULTS: Uric acid directly activates primary human T cells in the absence of antigen presentation. Furthermore, primary human T cells and Jurkat T cells treated with uric acid overexpress the costimulatory molecule CD70, which plays an important role in T cell-B cell interaction and antibody production. CONCLUSIONS: The finding that uric acid directly promotes T-cell activation in an antigen-independent system is novel and might play a mechanistic role in the inflammatory response observed in gouty arthritis and other immune-mediated diseases.

Activation antigens during the proliferative and secretory phases of endometrium and early-pregnancy decidua.

BACKGROUND: Clarifying the normal distribution of activation antigens will contribute to database construction studies of monoclonal-antibody-based therapies in endometrial disorders. METHODS: In this study, endometrial tissue samples obtained during proliferative and secretory phases and decidual samples of early pregnancies were immunostained by the monoclonal antibodies anti-CD26, anti-CD30, anti-CD70, anti-CD71, and anti-CD98 using the indirect immunoperoxidase method. RESULTS: CD26 is expressed on the glandular epithelium in the endometrium and decidua. Endothelial CD26 is expressed less in the decidua when compared to the endometrium. CD30 is strongly expressed by decidual cells. It is only weakly expressed on endometrial and decidual vessels. Glandular and endothelial CD70 expression is mainly seen in the proliferative phase of the menstrual cycle. Glandular CD71 expression is less in the decidua when compared to the endometrium. Its expression on stromal cells is more in the secretory phase of the menstrual cycle and in early pregnancy deciduae. It is expressed on endometrial vessels but not on decidual vessels. Glandular CD98 is expressed more in the decidua when compared to the endometrium. This antigen exists on endometrial lymphocytes. It is strongly expressed on the endothelium in the endometrium and decidua. CONCLUSION: It seems that CD26 and CD70 are not involved in the functions of endometrial and decidual stromal cells. CD30 and CD71 are thought to be involved in decidualization. Absence of activation antigens other than CD98 on lymphocytes indicated an antigenic profile for large granular lymphocytes that is different from regular lymphocytes.